CSS 3 Attribute Selectors
http://dev.opera.com/articles/view/css-3-attribute-selectors/

Schmitt, Christopher
Opera
2008

Abstract:

CSS attribute selectors allow us to pinpoint the values of attributes of an element and to style that element accordingly. CSS3 introduces three new selectors that can match strings against an attribute value at the beginning, the end, or anywhere within the value.This provides powerful new ways to style elements automatically that match very specific criteria. In this article, I will put these new attribute selectors in action and create some clever CSS rules that attach icons to links based on the value of the href attribute.